Publications (21)93.83 Total impact
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Article: Updating the Micro-Tom TILLING platform.
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ABSTRACT: The dwarf tomato variety Micro-Tom is regarded as a model system for functional genomics studies in tomato. Various tomato genomic tools in the genetic background of Micro-Tom have been established, such as mutant collections, genome information and a metabolomic database. Recent advances in tomato genome sequencing have brought about a significant need for reverse genetics tools that are accessible to the larger community, because a great number of gene sequences have become available from public databases. To meet the requests from the tomato research community, we have developed the Micro-Tom Targeting-Induced Local Lesions IN Genomes (TILLING) platform, which is comprised of more than 5000 EMS-mutagenized lines. The platform serves as a reverse genetics tool for efficiently identifying mutant alleles in parallel with the development of Micro-Tom mutant collections. The combination of Micro-Tom mutant libraries and the TILLING approach enables researchers to accelerate the isolation of desirable mutants for unraveling gene function or breeding. To upgrade the genomic tool of Micro-Tom, the development of a new mutagenized population is underway. In this paper, the current status of the Micro-Tom TILLING platform and its future prospects are described.Breeding Science 03/2013; 63(1):42-8. · 1.25 Impact Factor -
Article: Genes that influence yield in tomato.
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ABSTRACT: Yield is the most important breeding trait of crops. For fruit-bearing plants such as Solanum lycopersicum (tomato), fruit formation directly affects yield. The final fruit size depends on the number and volume of cell layers in the pericarp of the fruit, which is determined by the degree of cell division and expansion in the fertilized ovaries. Thus, fruit yield in tomato is predominantly determined by the efficiency of fruit set and the final cell number and size of the fruits. Through domestication, tomato fruit yield has been markedly increased as a result of mutations associated with fruit size and genetic studies have identified the genes that influence the cell cycle, carpel number and fruit set. Additionally, several lines of evidence have demonstrated that plant hormones control fruit set and size through the delicate regulation of genes that trigger physiological responses associated with fruit expansion. In this review, we introduce the key genes involved in tomato breeding and describe how they affect the physiological processes that contribute to tomato yield.Breeding Science 03/2013; 63(1):3-13. · 1.25 Impact Factor -
Article: A novel class of sticky peel and light green mutations causes cuticle deficiency in leaves and fruits of tomato (Solanum lycopersicum).
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ABSTRACT: The plant cuticle consists of aliphatic wax and cutin, and covers all the aerial tissues, conferring resistance to both biotic and abiotic stresses. In this study, we performed phenotypic characterizations of tomato mutants having both sticky peel (pe) and light green (lg) mutations. Our genetic analysis showed that these two mutations are tightly linked and behave like a monogenic recessive mutation. The double mutant (pe lg) produced glossy soft fruits with light green leaves, most likely due to defects in cuticle formation. Cytological analysis revealed that the thickness of the fruit cuticle layer was dramatically reduced in the pe lg mutant. The epidermal cells of the leaves were also deformed in the pe lg mutant, suggesting that leaf cuticle formation was also disrupted in the mutant. Consistent with this, transmission electron microscopic analysis showed that the electron density of the cuticle layer of the adaxial surface of the leaf was reduced in the pe lg mutant compared to WT, suggesting that there are changes in cuticle structure and/or composition in the pe lg mutant. Both physiological analysis to measure the rate of transpiration, and staining of the fruits and leaves with toluidine blue, revealed that water permeability was enhanced in the pe lg mutant, consistent with the reduced thickness of its cuticle layer. Taken together the preliminary analyses of the cuticle components, the PE LG is most likely involved in proper cuticle formation.Planta 07/2012; 236(5):1559-70. · 3.00 Impact Factor -
Article: Availability of Micro-Tom mutant library combined with TILLING in molecular breeding of tomato fruit shelf-life.
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ABSTRACT: Novel mutant alleles of an ethylene receptor Solanum lycopersicum ETHYLENE RESPONSE1 (SlETR1) gene, Sletr1-1 and Sletr1-2, were isolated from the Micro-Tom mutant library by TILLING in our previous study. They displayed different levels of impaired fruit ripening phenotype, suggesting that these alleles could be a valuable breeding material for improving shelf life of tomato fruit. To conduct practical use of the Sletr1 alleles in tomato breeding, genetic complementation analysis by transformation of genes carrying each allele is required. In this study, we generated and characterized transgenic lines over-expressing Sletr1-1 and Sletr1-2. All transgenic lines displayed ethylene insensitive phenotype and ripening inhibition, indicating that Sletr1-1 and Sletr1-2 associate with the ethylene insensitive phenotype. The level of ethylene sensitivity in the seedling was different between Sletr1-1 and Sletr1-2 transgenic lines, whereas no apparent difference was observed in fruit ripening phenotype. These results suggested that it is difficult to fine-tune the extent of ripening by transgenic approach even if the weaker allele (Sletr1-2) was used. Our present and previous studies indicate that the Micro-Tom mutant library combined with TILLING could be an efficient tool for exploring genetic variations of important agronomic traits in tomato breeding.Breeding Science 06/2012; 62(2):202-8. · 1.25 Impact Factor -
Article: Overexpression of the tomato glutamate receptor-like genes SlGLR1.1 and SlGLR3.5 hinders Ca 2 utilization and promotes hypersensitivity to Na and K stresses
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ABSTRACT: irteen glutamate receptor-like genes have recently been identiied in tomato plants; however, their functions have not been fully elucidated. We overexpressed SlGLR1.1 and SlGLR3.5 in Arabidopsis and found that transgenic plants showed symptoms such as curled and deformed leaves, dwarf stature and retarded growth resembling those of Ca 2+ deeciency. e results revealed that the levels of Ca 2+ in aerial tissues did not diier between wild-type and transgenic plants, suggesting that overexpression of SlGLR1.1 and SlGLR3.5 did not aect Ca 2+ uptake. Transgenic lines were hypersensitive to K + and Na + ionic stresses, which was rescued by addition of Ca 2+ to the growth medium. Ectopic expression of SlGLR1.1 and SlGLR3.5 resulted in reduced eciency of Ca 2+ utilization, suggesting that these genes may play a role in calcium assimilation in tomato plants by controlling ionic transport across the membrane.Plant Biotechnology 01/2012; 29:229-235. · 0.94 Impact Factor -
Article: Mapping of Micro-Tom BAC-End Sequences to the Reference Tomato Genome Reveals Possible Genome Rearrangements and Polymorphisms.
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ABSTRACT: A total of 93,682 BAC-end sequences (BESs) were generated from a dwarf model tomato, cv. Micro-Tom. After removing repetitive sequences, the BESs were similarity searched against the reference tomato genome of a standard cultivar, "Heinz 1706." By referring to the "Heinz 1706" physical map and by eliminating redundant or nonsignificant hits, 28,804 "unique pair ends" and 8,263 "unique ends" were selected to construct hypothetical BAC contigs. The total physical length of the BAC contigs was 495, 833, 423 bp, covering 65.3% of the entire genome. The average coverage of euchromatin and heterochromatin was 58.9% and 67.3%, respectively. From this analysis, two possible genome rearrangements were identified: one in chromosome 2 (inversion) and the other in chromosome 3 (inversion and translocation). Polymorphisms (SNPs and Indels) between the two cultivars were identified from the BLAST alignments. As a result, 171,792 polymorphisms were mapped on 12 chromosomes. Among these, 30,930 polymorphisms were found in euchromatin (1 per 3,565 bp) and 140,862 were found in heterochromatin (1 per 2,737 bp). The average polymorphism density in the genome was 1 polymorphism per 2,886 bp. To facilitate the use of these data in Micro-Tom research, the BAC contig and polymorphism information are available in the TOMATOMICS database.International Journal of Plant Genomics 01/2012; 2012:437026. -
Article: Tomato TILLING technology: development of a reverse genetics tool for the efficient isolation of mutants from Micro-Tom mutant libraries.
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ABSTRACT: To accelerate functional genomic research in tomato, we developed a Micro-Tom TILLING (Targeting Induced Local Lesions In Genomes) platform. DNA pools were constructed from 3,052 ethyl methanesulfonate (EMS) mutant lines treated with 0.5 or 1.0% EMS. The mutation frequency was calculated by screening 10 genes. The 0.5% EMS population had a mild mutation frequency of one mutation per 1,710 kb, whereas the 1.0% EMS population had a frequency of one mutation per 737 kb, a frequency suitable for producing an allelic series of mutations in the target genes. The overall mutation frequency was one mutation per 1,237 kb, which affected an average of three alleles per kilobase screened. To assess whether a Micro-Tom TILLING platform could be used for efficient mutant isolation, six ethylene receptor genes in tomato (SlETR1-SlETR6) were screened. Two allelic mutants of SlETR1 (Sletr1-1 and Sletr1-2) that resulted in reduced ethylene responses were identified, indicating that our Micro-Tom TILLING platform provides a powerful tool for the rapid detection of mutations in an EMS mutant library. This work provides a practical and publicly accessible tool for the study of fruit biology and for obtaining novel genetic material that can be used to improve important agronomic traits in tomato.Plant and Cell Physiology 09/2011; 52(11):1994-2005. · 4.70 Impact Factor -
Article: Mutations in the F-box gene SNEEZY result in decreased Arabidopsis GA signaling.
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ABSTRACT: We previously reported that the SLEEPY1 (SLY1) homolog, F-box gene SNEEZY/SLEEPY2 (SNE/SLY2), can partly replace SLY1 in gibberellin (GA) hormone signaling through interaction with DELLAs RGA and GAI. To determine whether SNE normally functions in GA signaling, we characterized the phenotypes of two T-DNA alleles, sne-t2 and sne-t3. These mutations result in no apparent vegetative phenotypes, but do result in increased ABA sensitivity in seed germination. Double mutants sly1-t2 sne-t2 and sly1-t2 sne-t3 result in a significant decrease in plant fertility and final plant height compared to sly1-t2. The fact that sne mutations have an additive effect with sly1 suggests that SNE normally functions as a redundant positive regulator of GA signaling.Plant signaling & behavior 06/2011; 6(6):831-3. -
Article: The role of two f-box proteins, SLEEPY1 and SNEEZY, in Arabidopsis gibberellin signaling.
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ABSTRACT: The SLEEPY1 (SLY1) F-box gene is a positive regulator of gibberellin (GA) signaling in Arabidopsis (Arabidopsis thaliana). Loss of SLY1 results in GA-insensitive phenotypes including dwarfism, reduced fertility, delayed flowering, and increased seed dormancy. These sly1 phenotypes are partially rescued by overexpression of the SLY1 homolog SNEEZY (SNE)/SLY2, suggesting that SNE can functionally replace SLY1. GA responses are repressed by DELLA family proteins. GA relieves DELLA repression when the SCF(SLY1) (for Skp1, Cullin, F-box) E3 ubiquitin ligase ubiquitinates DELLA protein, thereby targeting it for proteolysis. Coimmunoprecipitation experiments using constitutively expressed 35S:hemagglutinin (HA)-SLY1 and 35S:HA-SNE translational fusions in the sly1-10 background suggest that SNE can function similarly to SLY1 in GA signaling. Like HA-SLY1, HA-SNE interacted with the CULLIN1 subunit of the SCF complex, and this interaction required the F-box domain. Like HA-SLY1, HA-SNE coimmunoprecipitated with the DELLA REPRESSOR OF GA1-3 (RGA), and this interaction required the SLY1 or SNE carboxyl-terminal domain. Whereas HA-SLY1 overexpression resulted in a decrease in both DELLA RGA and RGA-LIKE2 (RGL2) protein levels, HA-SNE caused a decrease in DELLA RGA but not in RGL2 levels. This suggests that one reason HA-SLY1 is able to effect a stronger rescue of sly1-10 phenotypes than HA-SNE is because SLY1 regulates a broader spectrum of DELLA proteins. The FLAG-SLY1 fusion protein was found to coimmunoprecipitate with the GA receptor HA-GA-INSENSITIVE DWARF1b (GID1b), supporting the model that SLY1 regulates DELLA through interaction with the DELLA-GA-GID1 complex.Plant physiology 02/2011; 155(2):765-75. · 6.53 Impact Factor -
Article: TOMATOMA: a novel tomato mutant database distributing Micro-Tom mutant collections.
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ABSTRACT: The tomato is an excellent model for studies of plants bearing berry-type fruits and for experimental studies of the Solanaceae family of plants due to its conserved genetic organization. In this study, a comprehensive mutant tomato population was generated in the background of Micro-Tom, a dwarf, rapid-growth variety. In this and previous studies, a family including 8,598 and 6,422 M(2) mutagenized lines was produced by ethylmethane sulfonate (EMS) mutagenesis and γ-ray irradiation, and this study developed and investigated these M(2) plants for alteration of visible phenotypes. A total of 9,183 independent M(2) families comprising 91,830 M(2) plants were inspected for phenotypic alteration, and 1,048 individual mutants were isolated. Subsequently, the observed mutant phenotypes were classified into 15 major categories and 48 subcategories. Overall, 1,819 phenotypic categories were found in 1,048 mutants. Of these mutants, 549 were pleiotropic, whereas 499 were non-pleiotropic. Multiple different mutant alleles per locus were found in the mutant libraries, suggesting that the mutagenized populations were nearly saturated. Additionally, genetic analysis of backcrosses indicated the successful inheritance of the mutations in BC(1)F(2) populations, confirming the reproducibility in the morphological phenotyping of the M(2) plants. To integrate and manage the visible phenotypes of mutants and other associated data, we developed the in silico database TOMATOMA, a relational system interfacing modules between mutant line names and phenotypic categories. TOMATOMA is a freely accessible database, and these mutant recourses are available through the TOMATOMA (http://tomatoma.nbrp.jp/index.jsp).Plant and Cell Physiology 02/2011; 52(2):283-96. · 4.70 Impact Factor -
Article: Genetic suppression analysis in novel vacuolar processing enzymes reveals their roles in controlling sugar accumulation in tomato fruits.
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ABSTRACT: In plant cells, many vacuolar proteins are synthesized as precursors in the endoplasmic reticulum and are subsequently transported to the vacuole. These precursors are subject to post-translational modifications to allow the active mature forms to be produced. Vacuolar processing enzyme (VPE) has been identified as a family of cysteine proteases involved in protein maturation in the vacuole. In this study, novel VPE genes were isolated from tomato (Solanum lycopersicum), and they were designated SlVPE1-SlVPE5. Phylogenic analysis suggested that SlVPE1 and SlVPE2 were categorized as the seed coat type, SlVPE4 was categorized as the seed type, and both SlVPE3 and SlVPE5 were categorized as the vegetative type. Expression analysis demonstrated that these genes were expressed during fruit development, and that their expression profiles agreed with this classification. High VPE enzyme activity was observed during tomato fruit development; the enzyme activity was correlated with the SlVPE mRNA levels, indicating that the SlVPE encoded active VPE proteins. The total sugar content was higher in RNA interference (RNAi) lines compared with the control plants, suggesting negative roles for SlVPE in sugar accumulation. The quantitative expression analysis of each SlVPE gene in the RNAi lines suggested that the suppression of SlVPE5 probably had the strongest effect on the sugar accumulation observed. The suppression of SlVPE did not influence the total amino acid content, suggesting that the molecular targets of SlVPE were mainly involved in sugar accumulation.Journal of Experimental Botany 01/2011; 62(8):2773-86. · 5.36 Impact Factor -
Article: Genetic regulation of sporopollenin synthesis and pollen exine development.
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ABSTRACT: Pollen acts as a biological protector of male sperm and is covered by an outer cell wall polymer called the exine, which consists of durable sporopollenin. Despite the astonishingly divergent structure of the exine across taxa, the developmental processes of its formation surprisingly do not vary, which suggests the preservation of a common molecular mechanism. The precise molecular mechanisms underlying pollen exine patterning remain highly elusive, but they appear to be dependent on at least three major developmental processes: primexine formation, callose wall formation, and sporopollenin synthesis. Several lines of evidence suggest that the sporopollenin is built up via catalytic enzyme reactions in the tapetum, and both the primexine and callose wall provide an efficient substructure for sporopollenin deposition. Herein, we review the currently accepted understanding of the molecular regulation of sporopollenin biosynthesis and examine unanswered questions regarding the requirements underpinning proper exine pattern formation, as based on genetic evidence.Annual Review of Plant Biology 05/2010; 62:437-60. · 18.71 Impact Factor -
Article: Proteolysis-independent downregulation of DELLA repression in Arabidopsis by the gibberellin receptor GIBBERELLIN INSENSITIVE DWARF1.
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ABSTRACT: This article presents evidence that DELLA repression of gibberellin (GA) signaling is relieved both by proteolysis-dependent and -independent pathways in Arabidopsis thaliana. DELLA proteins are negative regulators of GA responses, including seed germination, stem elongation, and fertility. GA stimulates GA responses by causing DELLA repressor degradation via the ubiquitin-proteasome pathway. DELLA degradation requires GA biosynthesis, three functionally redundant GA receptors GIBBERELLIN INSENSITIVE DWARF1 (GID1a, b, and c), and the SLEEPY1 (SLY1) F-box subunit of an SCF E3 ubiquitin ligase. The sly1 mutants accumulate more DELLA proteins but display less severe dwarf and germination phenotypes than the GA biosynthesis mutant ga1-3 or the gid1abc triple mutant. Interestingly, GID1 overexpression rescued the sly1 dwarf and infertility phenotypes without decreasing the accumulation of the DELLA protein REPRESSOR OF ga1-3. GID1 rescue of sly1 mutants was dependent on the level of GID1 protein, GA, and the presence of a functional DELLA motif. Since DELLA shows increasing interaction with GID1 with increasing GA levels, it appears that GA-bound GID1 can block DELLA repressor activity by direct protein-protein interaction with the DELLA domain. Thus, a SLY1-independent mechanism for GA signaling may function without DELLA degradation.The Plant Cell 10/2008; 20(9):2447-59. · 8.99 Impact Factor -
Article: Ultrastructural characterization of exine development of the transient defective exine 1 mutant suggests the existence of a factor involved in constructing reticulate exine architecture from sporopollenin aggregates.
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ABSTRACT: A male-sterile mutant of Arabidopsis thaliana, in which filament elongation was defective although pollen fertility was normal, was isolated by means of T-DNA tagging. Transmission electron microscopy (TEM) analysis revealed that primexine synthesis and probacula formation, which are thought to be the initial steps of exine formation, were defective, and that globular sporopollenin aggregation was randomly deposited onto the microspore at the early uninucleate microspore stage. Sporopollenin aggregation, which failed to anchor to the microspore plasma membrane, was deposited on the locule wall and in the locule at the uninucleate microspore stage. However, visually normal exine with a basic reticulate structure was observed at the middle uninucleate microspore stage, indicating that the exine formation was restored in the mutant. Thus, the mutant was designated transient defective exine 1 (tde1). These results indicated that tde1 mutation affects the initial process of the exine formation, but does not impair any critical processes. Our results also suggest the existence of a certain factor responsible for exine patterning in A. thaliana. The TDE1 gene was found to be identical to the DE-ETIOLATED 2 gene known to be involved in brassinosteroid (BR) biosynthesis, and the tde1 probacula-defective phenotypes were recovered in the presence of BR application. These results suggest that BRs control the rate or efficiency of initial process of exine pattern formation.Plant and Cell Physiology 02/2008; 49(1):58-67. · 4.70 Impact Factor -
Article: Seed germination of GA-insensitive sleepy1 mutants does not require RGL2 protein disappearance in Arabidopsis.
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ABSTRACT: We explore the roles of gibberellin (GA) signaling genes SLEEPY1 (SLY1) and RGA-LIKE2 (RGL2) in regulation of seed germination in Arabidopsis thaliana, a plant in which the hormone GA is required for seed germination. Seed germination failure in the GA biosynthesis mutant ga1-3 is rescued by GA and by mutations in the DELLA gene RGL2, suggesting that RGL2 represses seed germination. RGL2 protein disappears before wild-type seed germination, consistent with the model that GA stimulates germination by causing the SCF(SLY1) E3 ubiquitin ligase complex to trigger ubiquitination and destruction of RGL2. Unlike ga1-3, the GA-insensitive sly1 mutants show variable seed dormancy. Seed lots with high seed dormancy after-ripened slowly, with stronger alleles requiring more time. We expected that if RGL2 negatively controls seed germination, sly1 mutant seeds that germinate well should accumulate lower RGL2 levels than those failing to germinate. Surprisingly, RGL2 accumulated at high levels even in after-ripened sly1 mutant seeds with 100% germination, suggesting that RGL2 disappearance is not a prerequisite for seed germination in the sly1 background. Without GA, several GA-induced genes show increased accumulation in sly1 seeds compared with ga1-3. It is possible that the RGL2 repressor of seed germination is inactivated by after-ripening of sly1 mutant seeds.The Plant Cell 04/2007; 19(3):791-804. · 8.99 Impact Factor -
Article: Abolition of the tapetum suicide program ruins microsporogenesis.
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ABSTRACT: Microsporogenesis in angiosperms takes places within the anther. Microspores are surrounded by a layer of cells, the tapetum, which degenerates during the later stages of pollen development with cytological features characteristic of programmed cell death (PCD). We report herein that the expression of AtBI-1, which suppresses Bax-induced cell death, in the tapetum at the tetrad stage inhibits tapetum degeneration and subsequently results in pollen abortion, while activation of AtBI-1 at the later stage does not. Our results demonstrate that the PCD signal commences at the tetrad stage and that the proper timing of PCD in the tapetum is essential for normal microsporogenesis.Plant and Cell Physiology 07/2006; 47(6):784-7. · 4.70 Impact Factor -
Article: The HKM gene, which is identical to the MS1 gene of Arabidopsis thaliana, is essential for primexine formation and exine pattern formation
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ABSTRACT: A male-sterile mutant of Arabidopsis thaliana was isolated by T-DNA tagging screening. Using transmission electron microscopy analysis, we revealed that the microspores of this mutant did not have normal thick primexine on the microspore at the tetrad stage. Instead, a moderately electron-dense layer formed around the microspores. Although microspores without normal primexine failed to form a proper reticulate exine pattern at later stages, sporopollenin was deposited and an exine-like hackly structure was observed on the microspores during the microspore stage. Thus, this mutant was named hackly microspore (hkm). It is speculated that the moderately electron-dense layer was primexine, which partially played its role in sporopollenin deposition onto the microspore. Cytological analysis revealed that the tapetum of the hkm mutant was significantly vacuolated, and that vacuolated tapetal cells crushed the microspores, resulting in the absence of pollen grains within the anther at anthesis. Single nucleotide polymorphism analysis demonstrated that the hkm mutation exists within the MS1 gene, which has been reportedly expressed within the tapetum. Our results suggest that the critical process of primexine formation is under sporophytic control .Sexual Plant Reproduction 05/2005; 18(1):1-7. · 1.87 Impact Factor -
Article: Disruption of the novel plant protein NEF1 affects lipid accumulation in the plastids of the tapetum and exine formation of pollen, resulting in male sterility in Arabidopsis thaliana.
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ABSTRACT: A novel male-sterile mutant of Arabidopsis thaliana was isolated by means of T-DNA tagging. Pollen abortion of the mutant was evident after microspore release, and pollen grains were completely absent at anthesis. Transmission electron microscope analysis revealed that primexine was coarsely developed, and that although sporopollenin was produced, it was not deposited onto the microspore plasma membrane. The sporopollenin that failed to be deposited aggregated and accumulated within the locule and on the locule wall. Finally, as no exine formation was observed, the mutant was named nef1. The plastoglobuli within the plastids of the tapetum were reduced, and lipid accumulation was considerably decreased. The mutant had a significantly altered leaf chloroplast ultrastructure and showed various growth defects. Lipid analysis revealed that the total lipid content in nef1 was lower than that in the wild type, which indicated that Nef1 was involved in lipid metabolism. Cloning of the full-length Nef1 indicated that the gene encodes a novel plant protein of 1123 amino acids with limited sequence similarities to membrane proteins or transporter-like proteins, and the NEF1 is predicted to be a plastid integral membrane protein. Motif analysis revealed that NEF1 contains prokaryotic membrane lipoprotein lipid attachment sites that are involved in maintaining cell envelope integrity. It is predicted that the Nef1 encodes a membrane protein that maintains the envelope integrity in the plastids.The Plant Journal 08/2004; 39(2):170-81. · 6.16 Impact Factor -
Article: A novel male-sterile mutant of Arabidopsis thaliana, faceless pollen-1, produces pollen with a smooth surface and an acetolysis-sensitive exine.
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ABSTRACT: A mutant exhibiting conditional male sterility, in which fertility was restored under conditions of high humidity, was identified in T-DNA tagged lines of Arabidopsis thaliana. Scanning electron microscopy (SEM) demonstrated that the pollen surface was almost smooth and the reticulate pattern not prominent. Thus, the mutant was named faceless pollen-1 (flp1). Transmission electron microscopy (TEM) revealed that the smooth appearance was due to tryphine filling in the exine cavities and covering the pollen surface. The lipid droplets in the tryphine of mutant pollen were smaller and more numerous than those of the wild type. SEM analysis also demonstrated that pollen exine was easily damaged by acetolysis, suggesting that a component of exine, sporopollenin, was defective in the mutant. In addition, the stems and siliques had reduced amounts of wax crystals. A predicted amino acid sequence of the cDNA that corresponded to the tagged gene, fip1, showed sequence similarity to proteins involved in wax biosynthesis. The FLP1 protein is likely to play a role in the synthesis of the components of tryphine, sporopollenin of exine and the wax of stems and siliques.Plant Molecular Biology 10/2003; 53(1-2):107-16. · 4.15 Impact Factor -
Article: Identification of anther-specific genes in a cruciferous model plant, Arabidopsis thaliana, by using a combination of Arabidopsis macroarray and mRNA derived from Brassica oleracea
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ABSTRACT: Arabidopsis thaliana, a member of the Brassicaceae, is a model plant whose genome was the first higher plant genome to be sequenced. Because of the small size of the flowers, it is difficult to dissect and separate reproductive organs (anthers and pistils) at different developmental stages in A. thaliana. In order to perform genome-wide identification of anther-specific genes in A. thaliana, an Arabidopsis cDNA macroarray was hybridized to cDNA derived from anthers and pistils of another crucifer, Brassica oleracea. After scanning the signal intensity for each clone, and cluster analysis, 52 anther-specific genes were identified. These clones contained several anther-specific genes that have already been characterized, as well as novel anther-specific genes. In RT-PCR analysis with mRNA of A. thaliana and B. oleracea, the expression pattern of one-third of the clones was similar to that determined by cDNA macroarray. This system of heterologous hybridization analysis (Arabidopsis cDNA macroarray vs Brassica tissue-specific mRNA) should be applicable to other model species and their close relatives.Sexual Plant Reproduction 12/2002; 15(5):213-220. · 1.87 Impact Factor
Top co-authors
Top Journals
Institutions
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2010–2012
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University of Tsukuba
Tsukuba, Ibaraki-ken, Japan
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2007–2011
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Washington State University
- Department of Crop and Soil Sciences
Pullman, WA, USA
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2002–2008
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Tohoku University
- Graduate School of Agricultural Science
Sendai-shi, Miyagi-ken, Japan
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2005
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Iwate Biotechnology Institute/Iwate Biotechnology Research Centre
Kitakami, Iwate-ken, Japan
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